A, B = map(int, input().split())

if A >= 12:
    A -= 12
# print(f'1 {A=} {B=}')
A *= 5
A += 60/12 * (B/60)
if A < B:
    A += 60

# print(f'2 {A=} {B=}')

p = 60 / (60 ** 2)
q = 60 / (60 * 60 * 12)
ans = (A - B) / (p - q)
print(int(ans))